Choosing pseudopotentials

For many elements several pseudopotential choices exist. The usual tradeoff between computational cost and accuracy and transferability applies. The choice of pseudopotential variant is not always straight forward. For the PBE generated latest PAW potential set (potpaw_PBE) we provide some recommendations for calculations involving a significant number of states far above the Fermi energy, and for those that are mainly evolved with states below or around the Fermi level.